Some of the commentary on the internet has been not especially well informed, for example there are some crazy claims at https://news.ycombinator.com/item?id=3668310. If you're in a "someone is wrong on the internet!" correcting mood, you might want to go leave some comments in furtherance of the collective intelligence of mankind.

I thought he made good points, but he quoted Meyer and Moran. I just think it's better that we're all informed as to the counter-arguments rather than ending up with egg on our faces.

I'm actually curious as to your specific objection/concern. I've read the various critiques written by detractors of the BAS tests over the years, but too many of those arguments relied on willful obtuseness and eye rolling. I'd like to hear the methodology/implementation critiques from those who nevertheless agreed with the conclusions.

The point has also been made that [in the article] first I argue "ultrasonics hurt fidelity" and then cite M&M, which supposedly undermines the argument because no one could hear a difference. In no way does M&M rebut the assertion that ultrasonics _can_ cause audible distortion. They were using high end setups designed at expense for audiophile-grade frequency extension, and the results show they obviously weren't affected by audible IMD. Am I missing something else?

I thought he made good points, but he quoted Meyer and Moran. I just think it's better that we're all informed as to the counter-arguments rather than ending up with egg on our faces.

I'm actually curious as to your specific objection/concern. I've read the various critiques written by detractors of the BAS tests over the years, but too many of those arguments relied on willful obtuseness and eye rolling. I'd like to hear the methodology/implementation critiques from those who nevertheless agreed with the conclusions.

The point has also been made that [in the article] first I argue "ultrasonics hurt fidelity" and then cite M&M, which supposedly undermines the argument because no one could hear a difference. In no way does M&M rebut the assertion that ultrasonics _can_ cause audible distortion. They were using high end setups designed at expense for audiophile-grade frequency extension, and the results show they obviously weren't affected by audible IMD. Am I missing something else?

Sorry, I haven't looked at this thread for a while.

The suggestion is not that M&M rebuts the assertion that ultrasonics can hurt fidelity but it demonstrates that ultrasonics did not hurt fidelity.

I don't suggest that the reference to M&M should have been omitted in order not to draw attention to the fact that it demonstrates that ultrasonics did not hurt fidelity, I merely draw attention to the fact that it demonstrates that ultrasonics did not hurt fidelity in the case examined.

The article contends that building to accommodate ultrasonics necessarily sacrifices performance in the audible range. This may be true, but it is not demonstrated that the degradation is audible. Technology, moreover, moves forward apace, so that even if there is audible degradation, this may not always be the case.

All this merely leads to the suggestion that equipment must necessarily be built to a higher standard i.e 'designed at expense for audiophile-grade frequency extension'.

While it is probably possible to establish reasonably accurately at what point THD becomes audible, it is preferable in some ways to sidestep any argument by exceeding the threshold of audibility by some margin, since, in the case of amplifiers anyway, this is technologically feasible. It may not be desirable to resist too strongly exceeding the threshold of audibility in terms of frequency response where this is feasible without degrading performance to the point where it no longer offers a margin over the threshold of audibility in other areas.